Want to chime in that I do get graphical glitches after a while, when playing through the EZ Flash Air. The firmware/kernel is up-to-date. Is 159FF629 still the checksum? I downloaded the latest version of Goodboy Galaxy and am getting "1b36ecf1" as checksum.
Edit: After running the checksum again, I get a different one. Something funky is going on!
Yet another edit: I've loaded the game onto NOR and manually setting the SAVE TYPE to SRAM, now I consistently get "90F6B869" as checksum. When loading the ROM into mGBA on my computer I get "159ff629". Setting the game to SRAM does seem to help, but needs some more research.